Frequently Asked Questions about SpaceOAR™ Hydrogel

You may have questions about how and why the procedure is done, and what to expect. This section will help to answer questions you may have about the procedure.

The rectum and prostate are in close proximity, which means during radiation therapy for prostate cancer the rectum may also be affected by radiation, potentially leading to issues with bowel function or other side effects.1 SpaceOAR Hydrogel is a polyethylene glycol (PEG) based absorbable hydrogel that temporarily creates space between the prostate and rectum. SpaceOAR Hydrogel is designed to reduce the radiation dose to the rectum and may help minimize the side effects of radiation therapy.2

SpaceOAR Hydrogel is an FDA-cleared medical device made mostly of water and polyethylene glycol (PEG) that, when combined, form a soft gel-like synthetic material.2 PEG is a material commonly used in other medical products.2 You should discuss any known allergies you may have to the SpaceOAR Hydrogel ingredients with your doctor.

More than 500 cancer centers around the world purchase SpaceOAR Hydrogel, with 220,000 patients to date and growing.*2

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By acting as a spacer, the hydrogel temporarily moves the rectum on average a half inch (1.3 cm) away from the prostate.2,3 By separating the prostate from the rectum, SpaceOAR Hydrogel is designed to reduce the radiation dose delivered to the rectum and may help minimize the side effects of radiation therapy.3

SpaceOAR Hydrogel can be implanted as an outpatient procedure in a hospital, surgery center, outpatient clinic, or doctor’s office prior to the start of radiation treatment.2 On average, the procedure itself is about 30 minutes.4

SpaceOAR Hydrogel is injected as a liquid through a needle inserted between the rectum and the prostate.2 It can be implanted via a local anesthetic that will numb the injection area or under general anesthesia that will put a patient to sleep during the procedure.3 SpaceOAR Hydrogel stays in place for about 3 months and is naturally absorbed into the body and removed through urine in about 6 months.2

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*Number of patients is based on units shipped and a BSC proprietary algorithm.

  1. Radiation Therapy for Prostate Cancer. American Cancer Society. https://www.cancer.org/cancer/prostate-cancer/treating/radiation-therapy.html. Accessed April 25, 2023.
  2. Data on file with Boston Scientific.
  3. Mariados N, Sylvester J, Shah D, et al. Hydrogel spacer prospective multicenter randomized controlled pivotal trial: dosimetric and clinical effects of perirectal spacer application in men undergoing prostate image guided intensity modulated radiation therapy. Int J Radiat Oncol Biol Phys. 2015 Aug 1;92(5):971–7.
  4. CMS 2023 Physician Worktime File. https://www.cms.gov/files/zip/cy-2023-pfs-final-rule-physician-work-time.zip. Accessed October 13, 2022.

Caution: U.S. Federal law restricts this device to sale by or on the order of a physician.

SpaceOAR Hydrogel is intended to temporarily move the rectal wall away from the prostate during the course of radiotherapy treatment for prostate cancer, and in creating this space it is the intent of SpaceOAR Hydrogel to reduce the radiation dose affecting the rectum.

SpaceOAR Hydrogel contains polyethylene glycol (PEG). As with any medical treatment, there are some risks involved with the use of SpaceOAR Hydrogel. Potential complications associated with SpaceOAR Hydrogel include, but are not limited to: pain associated with injection, pain or discomfort from the hydrogel, site inflammation, infection (including abscess), inability to urinate, urgent need to urinate, constipation, rectal muscle spasm, damage to lining of rectum, ulcers, fistula (a hole between rectum and bladder, urethra, or skin below the scrotum), perforation (hole in prostate, bladder, urethra, rectum), necrosis (dead tissue), allergic reaction (local reaction or more severe reaction, such as anaphylaxis), embolism (blood vessel blockage is possible and may happen outside of the pelvis, potentially impacting vital organs or legs), fainting, and bleeding. Please talk to your doctor about the risks and benefits related to using SpaceOAR Hydrogel. If one or more of these complications occur, you may need medical treatment or surgery. URO-1288805-AA

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